Parameter Class
===============

.. py:class:: Parameter(name, takes_boolean=False, default=None, value=None, required=False)
   :no-index:

Purpose
-------

``Parameter`` represents one declared equation function parameter.

Key concepts
------------

``takes_boolean``
   Marks the parameter as expecting a boolean expression.

``default`` / ``value`` / ``required``
   Define fallback behavior and whether a missing value is allowed.

Inherited helpers
-----------------

``get()``, ``is_empty()``, ``new(value)``

Examples
--------

.. code-block:: python

   from piethorn.math.equation import Parameter

   parameter = Parameter("amount", default=2)
   parameter.get()          # 2
   parameter.is_empty()     # False
   parameter.new(5).value   # 5